SafePlants

Interrupted Fern (Osmunda claytoniana)

The Interrupted Fern, scientifically known as Osmunda claytoniana, is a striking fern prized for its unique appearance and adaptability. Its common name refers to the "interrupted" look of its fronds caused by the presence of spore-bearing pinnae.

Considerations for Pets

• This plant produces spores.

Common Names

• Interrupted Fern
• Clayton's Fern
• Clayton's Flowering Fern

Nomenclature and Taxonomy

• Scientific Name: Osmunda claytoniana
• Family: Osmundaceae (Royal Fern Family)
• Order: Polypodiales
• Synonym: Osmunda interrupta
• French Name: Osmonde de Clayton

Distribution and Habitat

Osmunda claytoniana is native to both Eastern Asia and eastern North America, specifically the Eastern United States and Eastern Canada. In Mississippi, it is commonly found on moist, wooded slopes of ravines, moist sandstone ledges, and wet woodlands.

Morphological Characteristics and Growth Habits

• Deciduous perennial fern growing to a height of 0.5-1 meter (approximately 1.5-3 feet), sometimes reaching 4 feet.
• Forms a rosette of ascending to nearly erect leaves.
• Fronds are elliptic-oblong in shape and often approach 1 meter in length.
• Characterized by broad green fronds "interrupted" by spore-bearing pinnae (leaflets) in early summer.
• Fertile fronds have 2-5 pairs of pinnae in the center.
• Exhibits a conspicuously clumped growth form.
• Develops a vase-shaped habit similar in appearance to the Cinnamon Fern.
• Features a compact, wiry, horizontal rhizome.

Ecological Role

• Provides cover for wildlife.
• Frond leachates have allelopathic effects on ectomycorrhizal and nonmycorrhizal northern red oak.

Cultivation

• Hardy to zone (UK) 3.
• Prefers light (sandy), medium (loamy), and heavy (clay) soils.
• Prefers moist, rich, acidic soil typical of a healthy woodland but can adapt to drier soils and nearly full sun.
• Requires medium to high water use.
• Suitable for native gardens, raingardens, and shoreline stabilization.
• Prefers part-shade to full shade conditions.

Quirky Facts

• The Interrupted Fern gets its name from the distinctive appearance of its fronds, where the fertile leaflets interrupt the otherwise continuous green foliage.

Further Information

• Encyclopedia of Life: Comprehensive information and articles about Osmunda claytoniana.
• Dave's Garden: A community platform for sharing gardening tips and ideas.
• Tried and True Native Plant Selections for the Mid-Atlantic.